1. Field
The following description relates to a terminal device and a relay node selection method of the terminal device.
2. Description of the Related Art
Recently, a cooperative diversity system based on a distributed space-time coding (DSTC) to provide a spatial diversity gain in a wireless network has become the focus of attention.
Networking theories associated with a communication environment where a plurality of transmitting/receiving devices exists have been proposed since the early 1990s. As a variety of wireless network environments has been practically developed, networking theories for particular applications have been embodied.
A DSTC-based cooperative diversity system may have a superior link performance among nodes. Accordingly, DSTC schemes using spatial diversity based on an alamouti space time block code have been proposed. However, since such schemes may use a plurality of nodes between a source node and a destination node as relay nodes, system complexity may increase. Here, the source node may transmit data and the destination node may receive the data.
Another relay transmission system which may select an optimum relay node from a plurality of relay nodes to enable a source node and a destination node to perform communication through an optimum channel has been proposed. However, while such a relay transmission system may prevent excessive power consumption and provide a diversity gain, since a channel state between each relay node and a source node and a channel state between each relay node and a destination node are measured to select a relay node, system complexity may increase.